No heating and cold heater hose

[ollieconnect]

Excuse any stupid questions, bit of a newbie but enjoying learning as I go.

So picked up an 07 TDCI Connect a few weeks back, the first drive heating was all good but hasn't worked since then. The heater now only blows freezing cold air no matter what heat or fan speed it's set on. The engine temp dial always sits about a third up from cold, never gets to the middle. The left skinny heater hose pipe going from reservoir to top left of rad is cold, the other skinny hose is hot. Would this mean a blocked rad?

I've been trying to trouble shoot, here's what I've got so far:
There's a change in tone when you turn the temp dial so I think the flaps opening.
I've drained, flushed and filled the coolant plus removed and blown out the skinny heater hoses going to the reservoir.
Checked the fuse.
Thermostat has been changed.

I've tried to pump out any air as best as I can, but think there may still be some in there.
I want to check the hoses going to the heater matrix but can't see them, I know they go through the firewall, has anyone got a photo?

Thanks for any help, this has got me stumped!

[ollieconnect]

Bump, any ideas anyone? Changed thermostat again to make sure but still no luck

[Brains_transit]

When it's running can you see the fluid dropping from the top hose back in the cooling bottle cause if not it could be the water pump

[tez]

Bump, any ideas anyone? Changed thermostat again to make sure but still no luck

hv you checked the restrictor in the expansion near the h /tank as they get blocked some times